I am needing to build 27' trusses which include the soffits. I need the center height to be approx. 5'. What kind of truss should be built and what kind of details can you give me? I'd like to build these myself to save some money. Also, can I use all 2x4's or should I use 2x6's?

No on the 2x4 and you need to first check with your building department who issues permits. They may require engineered trusses. The safest bed I have used is to order one engineered truss, use it as a template and then copy it. Yahoo! Shopping Search Results for roof trusses (http://shopping.yahoo.com/search;_ylc=X3oDMTE2OHByMXZvBF9TAzc4NDcxODMzMQRrA0 NhbXBhaWduXzRecm9vZiB0cnVzc2Vz?p=roof+trusses&sem=google)

So, you don't think I could use 2x6's on the top chord and 2x4's on the rest? I thought about getting one made but not sure how much they will charge to make a deliver for only one.

2x4 is acceptable for the bottom span and most of the supports but not the top directly under the roofing. You must check the code in your area. I live in zone 5 and snow loads require us to be 2x8 with some pitches. http://www.public.iastate.edu/~mwps_dis/mwps_web/plans/truss_28.pdf